package medium;
/*
2.两数相加
 */
public class LeeCode02 {
  public static void main(String[] args) {

  }

  public ListNode addTwoNumbers(ListNode l1, ListNode l2) {

    ListNode prev = new ListNode(0);
    int carry = 0;
    ListNode cur = prev;
    while(l1 != null || l2 != null) {
      int n1 = l1 != null ? l1.val : 0;
      int n2 = l2 != null ? l2.val : 0;
      int sum = n1 + n2 + carry;
      carry = sum / 10;
      sum = sum % 10;
      cur.next = new ListNode(sum);
      cur = cur.next;
      if (l1 != null) {
        l1 = l1.next;
      }
      if (l2 != null) {
        l2 = l2.next;
      }
    }
    if (carry == 1) {
      cur.next = new ListNode(carry);
    }

    return prev.next;
  }

  class ListNode {
    int val;
    ListNode next;

    ListNode() {
    }

    ListNode(int val) {
      this.val = val;
    }

    ListNode(int val, ListNode next) {
      this.val = val;
      this.next = next;
    }
  }
}
